A steel production process, in general, consists of an ironmaking process, a steelmaking process, a continuous casting process, and a rolling process.
The aforementioned ironmaking process is a process wherein iron ore and coal for coke making, and flaming coal are inputted into a blast furnace with about a 100 m height, and a hot air of 1,200° C. is blew into the blast furnace, and the coal for coke making burns, while generating heat which melts iron ore into a molten metal. This molten metal is called a hot metal.
The aforementioned steelmaking process is a process wherein the molten metal (a hot metal) produced in the blast furnace is rich in carbon and contains impurities, for example, phosphorus (P) and sulfur(S), and scrap iron and hot metal are inputted together into a steel converter, and pure oxygen is blew in, thus eliminating phosphorous, sulfur and carbon components. A clean molten metal from which impurities have been eliminated, is called ingot steel.
The aforementioned continuous casting process is a process wherein a liquid state ingot steel is inputted into a mold and is passed through a continuous casting machine, thus being cooled and solidified, whereby an intermediate material, for example, a slab, a bloom, a billet, etc. can be continuously produced, and the bloom may be made into a billet via a steel piece rolling mill and may be made into rod wires via a rod wire rolling mill, and the slab may be made into a thick plate via a thick plate rolling mill or into a hot rolled steel sheet via a hot rolling mill.
The aforementioned rolling process is a process wherein the slab, bloom, billet, etc. which have been produced through the continuous casting process are passed through a plurality of rotating rolls, thus elongating and thinning such materials by continuously applying force to them. This rolling process may be categorized into a hot rolling method and a cold rolling method.
The steel production may produce a lot of chips (waste metals) and a lot of slag which might be used when melting and producing iron. These waste metals and slag are called a waste raw material (in the present invention, the waste raw material is collectively referred to waste metals contained in other industrial wastes, slag, etc.). They are simply sorted out as wastes and are intended to be disposed in these days.
Prior Art Documents (10-2000-0032398): An apparatus for producing an ingot which may be used for a pig iron when making steel by recycling chips or slag.
FIG. 1 is a front view schematically illustrating the aforementioned apparatus for producing an ingot which may be used for a pig iron when making steel by recycling chips or slag. FIG. 2 is a plane view of FIG. 1, and FIG. 3 is a partial cross sectional and enlarged front view illustrating a compression and formation unit in FIG. 1.
As illustrated in FIGS. 1 to 3, the aforementioned apparatus for producing an ingot which may be used for a pig ion when making steel by recycling chips and slag includes a sorting-out unit 7 adapted to sort out, depending on particle sizes, the waste into a raw material which may be used for the sake of recycling and a scrap iron which is not intended to be used; transfer units 9 and 11 adapted to transfer the raw material separated by the sorting-out unit 7 toward crushing units 13 and 15, which will be described later; crushing units 13 and 15 adapted to mix the raw material transferred from the transfer units 9 and 11 with a solidifier and transfer them while crushing; separating units 17 and 19 adapted to separate the raw material which has passed through the crushing units 13 and 15, into a raw material which will be re-crushed and a raw material which will be compressed and processed; an input and transfer unit 21 adapted to transfer the compression raw material, which has passed through the separating units 17 and 19, toward a compression and formation unit 27, which will be described later; feedback transfer units 23 and 25 adapted to feedback the re-crushing raw material, which has not passed through the separating units 17 and 19, toward the transferring unit 11, a compression and formation unit 27 adapted to compress into an ingot shape the compression raw material which has been supplied from the input and transfer unit 21; and a discharge and transfer unit 31 adapted to transfer the ingot, which has been compressed by the compression and formation unit 27, to a product pallet 29.
According to the aforementioned apparatus for producing an ingot which may be used for a pig ion when making steel by recycling chips and slag, it is very difficult to sort out the wastes into the materials for a raw material and a scrap iron while passing them through the sorting-out unit 7 which is adapted to sort out, depending on the particle sizes, the wastes into a raw material which will be used for recycling and a scrap iron which will not be used. Since the transfer units 9 and 11 adapted to transfer the raw material sorted out by the sorting-out unit 7 toward the crushing units 13 and 15 and the crushing units 13 and 15 adapted to mix the raw material transferred by the transfer units 9 and 11 with a solidifier and transfer them while crushing are employed, the aforementioned apparatus inevitably requires an additional component, for example, a solidifier, etc. Moreover, the aforementioned system may become complicated since the raw material should be passed through the separating units 17 and 19 which are adapted to separate the raw material, which has passed through the crushing units 13 and 15, into the materials for a re-crushing and a compression and process. The feedback transfer units 23 and 25 should be further provided, which are adapted to feedback toward the transfer unit 11 the raw material for re-crushing which has not passed through the separating units 17 and 19. For this reason, an over-complicated process and configuration are inevitable in the aforementioned conventional apparatus.